Method for generating electrochemically activated cleaning liquid

• US 8,012,340 B2
• Filed: 01/19/2007
• Issued: 09/06/2011
• Est. Priority Date: 02/10/2006
• Status: Active Grant

• Current Assignee: Tennant Company
• Original Assignee: Tennant Company
• Inventors: Field, Bruce F., Gronlund, Patrick J.
• Primary Examiner(s): Phasge; Arun S
• Application Number:
  US11/655,389
• Publication Number:
  US 20070186954A1
• Time in Patent Office: 1,691 Days
• Field of Search: 205/701, 205/746, 205755-757, 134/3, 134/10, 134/21, 134/36
• US Class Current: 205/746
• CPC Class Codes: A47L 11/305 the tools being disc brushes
• CPC Class Codes: A47L 11/4016 specially adapted for collecting fluids
• CPC Class Codes: A47L 11/4038 Disk shaped surface treating tools
• CPC Class Codes: A47L 11/4044 Vacuuming or pick-up tools; Squeegees
• CPC Class Codes: A47L 11/4083 Liquid supply reservoirs; Preparation of the agents, e.g. mixing devices
• CPC Class Codes: C11D 2111/46 applying energy, e.g. irradiation

Abstract

A method is provided, which includes moving a mobile floor cleaning device along a floor; electrochemically activating a liquid on the mobile floor cleaning device, and dispensing the electrochemically activated liquid from the mobile floor cleaning device.

Claims

1. A method comprising:

a) moving a mobile floor cleaning device along a floor;

b) electrochemically activating a liquid on the mobile floor cleaning device by converting the liquid into an anolyte electrochemically activated (EA) liquid and a catholyte EA liquid with a functional generator comprising an ion exchange membrane, where the anolyte EA liquid and the catholyte EA liquid have oxidation reduction potentials (ORPs) outside a range of ±

50 mV;

c) combining all of the anolyte and catholyte EA liquid produced in step b) to form a combined anolyte and catholyte liquid on the device without an intermediate step of storing either of the anolyte or catholyte liquids produced in step b), wherein the combined anolyte and catholyte liquid neutralizes to an ORP between ±

50 mV within 1 minute from the time the anolyte EA liquid and the catholyte EA liquid are produced by the functional generator; and

d) dispensing substantially all of the combined anolyte and catholyte liquid from the mobile floor cleaning device upon electrical activation in step b), while moving the mobile floor cleaning device in step a).

2. The method of claim 1, wherein the mobile floor cleaning device comprises a motorized cleaning head comprising a cleaning tool, and wherein dispensing in step d) comprises:

dispensing the combined anolyte and catholyte liquid to at least one of the floor, the cleaning tool or both the floor and the cleaning tool.

3. The method of claim 1 wherein electrochemically activating the liquid in step b) comprises:

passing the liquid through the functional generator carried by the mobile floor cleaning device, which comprises an anode chamber and a cathode chamber that are separated by the ion exchange membrane, wherein the anode chamber generates anolyte EA liquid and the cathode chamber generates catholyte EA liquid.

4. The method of claim 3 wherein the functional generator in step b) comprises a first plurality of anode chambers and a second plurality of cathode chambers.

5. The method of claim 3 wherein the passing comprises pumping the liquid from a tank carried by the mobile floor cleaning device through the functional generator, which is activated by a control circuit during a first operating mode when the device is in motion relative to the floor and is de-activated during a second operating mode when the device is at rest relative to the floor.

6. The method of claim 3 and further comprising:

applying a voltage across electrodes in the anode and cathode chambers; and

periodically alternating relative polarities of the anode and cathode for equal time periods at each polarity to produce a ratio of essentially one part anolyte to one part catholyte in the combined anolyte and catholyte liquid.

7. The method of claim 1 and further comprising:

d) performing steps b), c) and d) during a first operating mode while moving the mobile floor cleaning device along the floor in step a); and

e) disabling steps b), c) and d) during a second operating mode when the mobile floor cleaning device is at rest relative to the floor.

8. The method of claim 1, wherein the liquid of step b) consists essentially of tap water.

9. The method of claim 1, wherein the liquid of step b) consists of tap water.

10. The method of claim 1, wherein the liquid of step b) comprises water and an electrolyte concentration that is greater than zero and does not exceed 1.0 moles per liter.

11. The method of claim 1 and further comprising:

e) sparging the liquid of step b) prior to performing step b), sparging the combined anolyte and catholyte liquid, or both sparging the liquid of step b) prior to performing step b) and sparging the combined anolyte and catholyte liquid.

12. The method of claim 11 wherein the sparging of step d) comprises oxygenating by electrolysis the liquid of step b) prior to performing step b) with an electrolysis cell that lacks an ion exchange membrane.

13. The method of claim 1 and further comprising:

e) scrubbing the floor with a motorized scrubbing tool selected from the group consisting of a hard floor scrub brush, a soil transfer roller and a soft floor extraction tool.

14. The method of claim 1 and further comprising:

e) recovering at least a portion of the electrochemically activated liquid from the floor using a recovery system carried by the device.

15. The method of claim 14, wherein the recovery system is selected from the group comprising:

a vacuum squeegee that engages the floor;

a vacuum extractor that engages the floor; and

a vacuum extractor that recovers at least a portion of the liquid from a cleaning tool, which is carried by the mobile floor cleaning device and engages the floor.

16. The method of claim 1, wherein upon production by the functional generator, the anolyte EA liquid has an ORP in a range of +100 mV to +1200 mV, and the catholyte EA liquid has an ORP in a range of −

150 mV to −

1000 mV.

17. The method of claim 1, wherein step d) comprises dispensing substantially all of the combined anolyte and catholyte liquid from the mobile floor cleaning device within 5 seconds of electrical activation in step b).

18. The method of claim 1, wherein step d) comprises dispensing substantially all of the combined anolyte and catholyte liquid from the mobile floor cleaning device within 3 seconds of electrical activation in step b).

19. A method comprising:

a) onboard an apparatus, converting water into an anolyte electrochemically activated (EA) liquid and a catholyte EA liquid with a functional generator having an anode and a cathode separated by an ion exchange membrane, where the anolyte EA liquid and the catholyte EA liquid have oxidation reduction potentials (ORPs) outside a range of ±

50 mV;

b) onboard the apparatus, combining all of the anolyte EA liquid with all of the catholyte EA liquid to form a combined anolyte and catholyte EA liquid, wherein the combined anolyte and catholyte EA liquid neutralizes to an ORP between ±

50 mV within 1 minute from the time the anolyte EA liquid and the catholyte EA liquid are produced by the functional generator;

c) periodically alternating relative polarities of a relatively steady state voltage applied to the anode and cathode for equal time periods at each polarity during the step of passing to produce a ratio of essentially one part of the anolyte EA liquid to one part of the catholyte EA liquid in the combined anolyte and catholyte EA liquid; and

d) dispensing the combined anolyte and catholyte EA liquid from the apparatus.

20. The method of claim 19 wherein the apparatus comprises a mobile cleaning apparatus and wherein the method further comprises:

e) moving a mobile cleaning apparatus along a surface during steps a) through d).

21. The method of claim 20, wherein the mobile cleaning apparatus comprises a motorized cleaning head comprising a cleaning tool, and wherein step d) comprises:

dispensing the combined anolyte and catholyte EA liquid to at least one of the surface, the cleaning tool or both the surface and the cleaning tool.

22. The method of claim 20 and further comprising:

e) storing the water in a tank carried by the mobile cleaning apparatus; and

f) pumping the water from the tank during steps a) through d).

23. The method of claim 20 and further comprising:

f) performing steps a) through d) during a first operating mode while moving the mobile cleaning apparatus along the surface in step e); and

g) disabling steps a) through d) during a second operating mode when the mobile cleaning apparatus is at rest relative to the surface.

24. The method of claim 20 and further comprising:

f) scrubbing the surface with a motorized scrubbing tool selected from the group consisting of a hard surface scrub brush, a soil transfer roller and a soft surface extraction tool.

25. The method of claim 19, wherein the water consists essentially of tap water.

26. The method of claim 19, wherein the water consists of tap water.

27. The method of claim 19, wherein the water comprises an electrolyte concentration that is greater than zero and does not exceed 1.0 moles per liter.

28. The method of claim 19 and further comprising:

d) sparging the water prior to performing step a), sparging at least one of the anolyte EA liquid or the catholyte EA liquid, or both sparging the water prior to performing step a) and sparging at least one of the anolyte EA liquid or the catholyte EA liquid.

29. The method of claim 28 wherein the sparging of step d) comprises oxygenating by electrolysis.

30. The method of claim 19 and further comprising:

e) recovering at least a portion of the combined anolyte and catholyte EA liquid from a surface using a recovery system coupled to the apparatus.

31. The method of claim 30, wherein the recovery system is selected from the group comprising:

a vacuum squeegee that engages the surface;

a vacuum extractor that engages the surface;

a vacuum extractor that recovers at least a portion of the combined liquid from a cleaning tool, which is carried by the apparatus and engages the surface; and

a wand.

32. The method of claim 19 wherein:

combining in step b) comprises alternating a flow of the anolyte EA liquid with a flow of the catholyte EA liquid along a combined flow path.

33. The method of claim 19, wherein upon conversion by the functional generator, the anolyte EA liquid has an ORP in a range of +100 mV to +1200 mV, and the catholyte EA liquid has an ORP in a range of −

150 mV to −

1000 mV.

34. The method of claim 19, wherein step d) comprises dispensing substantially all of the combined anolyte and catholyte liquid from the apparatus within 5 seconds of electrical activation in step b).

35. The method of claim 19, wherein step d) comprises dispensing substantially all of the combined anolyte and catholyte liquid from the apparatus within 3 seconds of electrical activation in step b).

36. A method comprising:

a) on an apparatus, converting a liquid into an anolyte electrochemically activated (EA) liquid and a catholyte EA liquid with a functional generator comprising an ion exchange membrane, where the anolyte EA liquid and the catholyte EA liquid have oxidation reduction potentials (ORPs) outside a range of ±

50 mV;

b) upon conversion in step a), combining all of the anolyte EA liquid with all of the catholyte EA liquid on the apparatus without valving to form a combined anolyte and catholyte EA liquid, wherein the combined anolyte and catholyte EA liquid neutralizes to an ORP between ±

50 mV within 1 minute from the time the anolyte EA liquid and the catholyte EA liquid are produced by the functional generator;

c) dispensing substantially all of the combined anolyte and catholyte EA liquid from the apparatus to a surface within 5 seconds of conversion in step a) without an intermediate step of storing the combined anolyte and catholyte EA liquid, the anolyte EA liquid or the catholyte liquid; and

d) cleaning a surface with the combined anolyte and catholyte EA liquid.

37. The method of claim 36 and further comprising:

e) converting in step a) with the functional generator having an anode and a cathode separated by the ion exchange membrane; and

f) periodically alternating relative polarities of a relatively steady state voltage applied to the anode and cathode for equal time periods at each polarity during the step of converting to produce a ratio of essentially one part of the anolyte EA liquid to one part of the catholyte EA liquid in the combined anolyte and catholyte EA liquid.

38. The method of claim 36, wherein upon conversion by the functional generator, the anolyte EA liquid has an ORP in a range of +100 mV to +1200 mV, and the catholyte EA liquid has an ORP in a range of −

150 mV to −

1000 mV.

39. The method of claim 36, wherein step c) comprises dispensing substantially all of the combined anolyte and catholyte liquid from the apparatus within 3 seconds of conversion in step a).